U.S. Pat. Nos. 3,271,299 and 3,342,750 describe methods for producing colloidal hydrogels of aluminum phosphate which are employed as catalyst supports.
U.S. Pat. No. 3,904,550 discloses a method of precipitating aluminum phosphates from aluminum alkoxides with a phosphorus containing acid to give relatively high surface area supports.
The prior art, however, does not suggest or teach the preparation of a phospha-alumina gel, wherein such gel, when formed and calcined, (a) has a large average pore diameter, (in excess of 100 A) as determined by nitrogen adsorption and mercury intrusion methods, (b) having a characteristic pore volume distribution with a minimum number of small pores, such that less than 30% of the total pore volume is in pores smaller than 100 A in diameter, and (c) which can be prepared using inorganic aluminum salts and inorganic water soluble phosphates as starting materials.